Rosegarden
If you want to use MIDI to create and edit music, Rosegarden is one of the best programs available for Linux. It’s a complete sequencer, along with a multitrack editor, and supports both piano-roll and score notation. Figure 14-11 shows the program editing aveverum.rg, one of the sample files that comes with it.

Figure 14-11. Editing a MIDI file with Rosegarden
On the left of the window are three panes for controlling one or more of the current track segment’s parameters, the parameters of the whole track, or the instruments used. In the center, the instruments used are shown, with round checkboxes next to them for selecting muting or recording.
The righthand pane shows a piano roll representing the entire track. Using the slider above it, you can zoom in and out of the track to see more or less detail. The buttons in the top toolbar offer many powerful extra options, such as calling up the MIDI Mixer shown in Figure 14-12.

Figure 14-12. The Rosegarden MIDI Mixer
Other features include a percussion matrix editor, an audio mixer, and a musical notation editor, as shown in Figure 14-13, with which you can make beautiful-looking scores. Because of all these powerful features, the application takes a little while to learn, but the rewards are well worth the time spent doing so.
Figure 14-13. The ...